c语言菜单学生信息管理系统

Question

编写c语言代码，向系统输入要求，并且有输出部分。实现插入修改删除，输出学生数据，

Answer 1

#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>    /*I/O函数*/
#include<stdlib.h>    /*其它说明*/
#include<string.h>    /*字符串函数*/

#define LEN 15        /* 学号和姓名最大字符数,实际请更改*/
#define N 50        /* 最大学生人数,实际请更改*/

int k = 1, n = 0, m = 0;/* n代表当前记录的学生人数*/

//函数声明
void readfile();
void seek();
void modify();
void insert();
void del();
void display();
void save();
void menu();

//结构体保存学生信息
struct student{
    char StudentId[LEN+1];
    char StudentName[LEN+1];
    int StudentAge;
    char StudentSex;
    float score[3];
}stu[N];

//主函数
int main()
{
    while (k)
    {
        menu();
    }
    system("pause");
    return 0;
}

//系统帮助函数
void help()
{
    printf("\n0.欢迎使用系统帮助！\n");
    printf("\n1.初次进入系统后,请先选择增加学生信息;\n");
    printf("\n2.按照菜单提示键入数字代号;\n");
    printf("\n3.增加学生信息后,切记保存;\n");
    printf("\n4.谢谢您的使用！\n");
}

//刷新文件
int flush(){
    char filename[LEN + 1];
    int i = 0;
    printf("请输入要刷新学生信息的文件名：\n");
    scanf("%s", filename);
    int j = 0;
    FILE * fp;
    if ((fp = fopen(filename, "r")) == NULL) return 0;
    //从文件读取信息 
    while (fscanf(fp, "%s %s %s %d %d %d %d ", &stu[j].StudentId, &stu[j].StudentName, &stu[j].StudentAge, &stu[j].StudentSex, &stu[j].score[0], &stu[j].score[1], &stu[j].score[2]) == 7) {
        j++;
    }
    n = j;
    printf("刷新成功!!!");
    return n;
}

//查找学生信息
void seek() /*查找*/
{
    int i, item, flag;
    char s1[21]; /* 以姓名和学号最长长度+1为准*/
    printf("------------------\n");
    printf("-----1.按学号查询-----\n");
    printf("-----2.按姓名查询-----\n");
    printf("-----3.退出本菜单-----\n");
    printf("------------------\n");
    while (1)
    {
        printf("请选择子菜单编号:");
        scanf("%d", &item);
        flag = 0;
        switch (item)
        {
        case 1:
            printf("请输入要查询的学生的学号:\n");
            scanf("%s", s1);
            for (i = 0; i<n; i++)
            if (strcmp(s1,stu[i].StudentId) == 0)
            {
                flag = 1;
                printf("学生学号\t学生姓名\t年龄\t性别\tC语言成绩\t高等数学\t大学英语成绩\n");
                printf("--------------------------------------------------------------------\n");
                printf("%s\t%s\t%d\t%6\t%.1f\t%.1f\t%.1f\n", stu[i].StudentId,stu[i].StudentName,stu[i].StudentAge,stu[i].StudentSex,stu[i].score[0],stu[i].score[1],stu[i].score[2]);
            }
            if (0 == flag)
                printf("该学号不存在！\n"); break;
        case 2:
            printf("请输入要查询的学生的姓名:\n");
            scanf("%s", s1);
            for (i = 0; i<n; i++)
            if (strcmp(stu[i].StudentName, s1) == 0)
            {
                flag = 1;
                printf("学生学号\t学生姓名\t年龄\t性别\tC语言成绩\t高等数学\t大学英语成绩\n");
                printf("--------------------------------------------------------------------\n");
                printf("%s\t%s\t%d\t%c\t%.1f\t%.1f\t%.1f\n", stu[i].StudentId, stu[i].StudentName, stu[i].StudentAge, stu[i].StudentSex, stu[i].score[0], stu[i].score[1], stu[i].score[2]);
            }
            if (0 == flag)
                printf("该姓名不存在！\n"); break;
        case 3:return;
        default:printf("请在1-3之间选择\n");
        }
    }
}

//修改学生信息
void modify() /*修改信息*/
{
    int i, item, num = -1;
    char sex1, s1[LEN + 1], s2[LEN + 1]; /* 以姓名和学号最长长度+1为准*/
    float score1;
    printf("请输入要要修改的学生的学号:\n");
    scanf("%s", s1);
    for (i = 0; i < n; i++){
        if (strcmp(stu[i].StudentId, s1) == 0){/*比较字符串是否相等*/
            num = i;
            printf("------------------\n");
            printf("1.修改姓名\n");
            printf("2.修改年龄\n");
            printf("3.修改性别\n");
            printf("4.修改C语言成绩\n");
            printf("5.修改高等数学成绩\n");
            printf("6.修改大学英语成绩\n");
            printf("7.退出本菜单\n");
            printf("------------------\n");
            while (1)
            {
                printf("请选择子菜单编号:");
                scanf("%d", &item);
                switch (item)
                {
                case 1:
                    printf("请输入新的姓名:\n");
                    scanf("%s", s2);
                    strcpy(stu[num].StudentName, s2);
                    break;
                case 2:
                    printf("请输入新的年龄:\n");
                    scanf("%d", stu[num].StudentAge);
                    break;
                case 3:
                    printf("请输入新的性别:\n");
                    scanf("%s", &sex1);
                    stu[i].StudentSex = sex1;
                    break;
                case 4:
                    printf("请输入新的C语言成绩:\n");
                    scanf("%f", &score1);
                    stu[num].score[0] = score1;
                    break;
                case 5:
                    printf("请输入新的高等数学成绩:\n");
                    scanf("%f", &score1);
                    stu[num].score[1] = score1;
                    break;
                case 6:
                    printf("请输入新的大学英语成绩:\n");
                    scanf("%f", &score1);
                    stu[num].score[2] = score1;
                    break;
                case 7:    return;
                default:printf("请在1-7之间选择\n");
                }
            }
            printf("修改完毕！请及时保存！\n");
        }
        else{
            printf("没有该学生学号!!!");
        }
    }
}

void sort()//按学号排序
{
    int i, j, k, *p, *q, s;
    char temp[LEN + 1], ctemp;
    float ftemp;
    for (i = 0; i<n - 1; i++)
    {
        for (j = n - 1; j>i; j--)
        if (strcmp(stu[j - 1].StudentId, stu[j].StudentId)>0)
        {
            strcpy(temp, stu[j - 1].StudentId);
            strcpy(stu[j - 1].StudentId, stu[j].StudentId);
            strcpy(stu[j].StudentId, temp);
            strcpy(temp, stu[j - 1].StudentName);
            strcpy(stu[j - 1].StudentName, stu[j].StudentName);
            strcpy(stu[j].StudentName, temp);
            ctemp = stu[j - 1].StudentSex;
            stu[j - 1].StudentSex = stu[j].StudentSex;
            stu[j].StudentSex = ctemp;
            p = &stu[j - 1].StudentAge;
            q = &stu[j].StudentAge;
            s = *q;
            *q = *p;
            *p = s;
            for (k = 0; k<3; k++)
            {
                ftemp = stu[j - 1].score[k];
                stu[j - 1].score[k] = stu[j].score[k];
                stu[j].score[k] = ftemp;
            }
        }
    }
}

//添加学生信息函数
void insert() /*插入函数*/
{
    int i = n, j, flag;
    printf("请输入待增加的学生数:\n");
    scanf("%d", &m);
    if (m > 0){
        do
        {
            flag = 1;
            while (flag)
            {